Reducing the use of drugs would be better tackled by having a bigger welfare state, rather than criminalising addicts, according to research.

The work, published today, shows countries that provide a generous social security system have low levels of injecting drug use, irrespective of how punitive the drugs policy is. Charities have used the study to argue that the government's welfare cuts will see a rise in drug addicts.

Alex Stevens, professor in criminal justice at the University of Kent, said countries that imprison swaths of drug offenders and that have a limited welfare state, such as the US and to a lesser extent, the UK, consistently have "serious drug problems". However, countries such as Germany and the Netherlands, which offer generous benefits, have dramatically curbed the spread of hard drugs such as heroin.

Stevens said his book, Drugs, Crime and Public Health, showed social inclusion was needed to reduce drug use, rather than a programme of "mass incarceration".

There are two reasons, he said, why welfare is so important: regular benefits keep people out of a criminal underclass and the welfare state allows addicts to kick the habit by bringing stability to their lives. "Making sure users have a roof over their heads means they can be enrolled in programmes to get them off drugs."

Neil McKechnie, professor of drug misuse research at Glasgow University, said this was a "highly questionable analysis".

He said: "It is a rather old Labour way of thinking that poverty or deprivation is the explanation for drug use. The reality is that many people have difficult lives but they are not all taking drugs. Policy is important and I think that we have not tried abstinence, really enforced it."

But charities welcomed the research. Martin Barnes, chief executive of DrugScope, said: "At a time of spending cuts and social reform, it is timely evidence of the importance of the benefits system in both mitigating and preventing social and health problems, thereby reducing longer-term costs to society."